As is known, the rear seats of motor vehicles define the front surface of the luggage compartment and must therefore be sufficiently robust to withstand impact forces of the luggage against said surface in case of sudden braking or even in the event of an accident. For that purpose, the rear seats have a padding with a padding cover and a rear structure, that supports the padding and is made of metal material. Said structure normally comprises a substantially vertical plate, to which the edge of the cover is attached, and a tubular element, which extends in a circular fashion on the front surface of the plate and is welded to said plate. Lastly, a panel made of plastic material covers the rear surface of the plate of the metal structure, so as to define an aesthetic finish towards the luggage compartment.
To assemble the structure, during welding operations the plate and the tubular element must be held in contact, in relatively fixed positions, involving the use of relatively complex and expensive equipment.